import shutil
import unittest
from pathlib import Path

from composectl import (
    build_compose_command,
    build_update_commands,
    detect_runtime,
    discover_compose_files,
    discover_stack_names,
)


class ComposeCtlTests(unittest.TestCase):
    def test_detect_runtime_returns_installed_backend(self):
        runtime = detect_runtime()
        expected = "docker" if shutil.which("docker") else "podman"
        self.assertEqual(runtime, expected)

    def test_detect_runtime_rejects_unavailable_explicit_runtime(self):
        if shutil.which("docker"):
            self.skipTest("Docker is available on this host")
        with self.assertRaises(RuntimeError):
            detect_runtime(preferred="docker")

    def test_build_compose_command_uses_selected_runtime(self):
        cmd = build_compose_command(
            runtime="podman",
            compose_file=Path("services/media_rhel1/compose.yaml"),
            project_name="media_rhel1_services",
            action="up",
        )
        self.assertEqual(
            cmd,
            [
                "podman",
                "compose",
                "-f",
                "services/media_rhel1/compose.yaml",
                "-p",
                "media_rhel1_services",
                "up",
                "-d",
                "--remove-orphans",
            ],
        )

    def test_discover_compose_files_finds_existing_stacks(self):
        stack_files = discover_compose_files(Path("."))
        self.assertIn(Path("services/media_nas1/compose.yaml"), stack_files)
        self.assertIn(Path("services/media_rhel1/compose.yaml"), stack_files)

    def test_discover_stack_names_returns_inferred_stack_names(self):
        stack_names = discover_stack_names(Path("."))
        self.assertIn("media_nas1", stack_names)
        self.assertIn("media_rhel1", stack_names)

    def test_build_update_commands_returns_full_stack_refresh_sequence(self):
        commands = build_update_commands(
            runtime="podman",
            compose_file=Path("services/media_rhel1/compose.yaml"),
            project_name="media_rhel1_services",
        )
        self.assertEqual(
            commands,
            [
                ["podman", "compose", "-f", "services/media_rhel1/compose.yaml", "-p", "media_rhel1_services", "config"],
                ["podman", "compose", "-f", "services/media_rhel1/compose.yaml", "-p", "media_rhel1_services", "pull"],
                ["podman", "compose", "-f", "services/media_rhel1/compose.yaml", "-p", "media_rhel1_services", "up", "-d", "--remove-orphans"],
            ],
        )

    def test_build_update_commands_can_include_image_prune(self):
        commands = build_update_commands(
            runtime="docker",
            compose_file=Path("services/media_nas1/compose.yaml"),
            project_name="media_nas1_services",
            prune=True,
        )
        self.assertEqual(commands[-1], ["docker", "image", "prune", "-f"])

    def test_build_compose_command_can_validate_configuration(self):
        command = build_compose_command(
            runtime="docker",
            compose_file=Path("services/media_nas1/compose.yaml"),
            project_name="media_nas1_services",
            action="config",
        )
        self.assertEqual(command[-1], "config")


if __name__ == "__main__":
    unittest.main()